Method and apparatus for diverting flow in a downhole pump

ABSTRACT

The present invention comprises an apparatus for diverting flow in a downhole pump and a method for using the apparatus. A sucker rod lifting system includes a valve rod guide having a sleeve that helps divert fluid as it passes through the rod guide to minimize damage to the system tubing. The diverter sleeve may encircle discharge ports on the valve rod guide such that fluid discharging through the ports is directed upwardly past the sleeve and out a discharge gap on the upper end of the guide. Used in this manner, the diverter sleeve prevents the fluid from damaging system tubing as it moves through the rod guide.

FIELD

The present invention relates to pumps. More specifically, it relates to an apparatus for diverting flow in a downhole pump.

BACKGROUND

A number of technologies exist for pumping liquids and mixtures stored underground. A common method for pumping oil and water from ground wells is a downhole pump that utilizes a sucker rod lifting system. The downhole components of a sucker rod system include generally: tubing for transporting the liquid to the surface, a pump barrel with a one-way valve, a pump plunger with a one-way valve, and one or more sucker rods. The sucker rod may consist of a rod string portion and a valve rod portion. The valve rod portion typically connects to the plunger and is routed through a valve rod guide.

In general, the rods are connected to the plunger and move it up and down to deliver the underground liquid through the tubing to the surface. The sucker rod system works on the premise that the liquid being pumped will be drawn into the barrel, and during the downstroke, the plunger moves into the barrel and collects liquid into the plunger. During the upstroke, the plunger lifts the liquid while also drawing more liquid into the barrel. The constant lifting of liquid by the plunger and drawing more liquid into the barrel moves or pumps the liquid to the surface.

One problem with the sucker rod system is that there are areas in the system where the liquid being pumped moves at a relatively high velocity and pressure compared to the rest of the system, which can damage certain components of the system. For example, as liquid is lifted by the plunger, it is typically forced through openings in the valve rod guide. As the liquid passes through the openings, it tends to increase in velocity which can create jets or streams that are directed against the tubing in the system. The streams are particularly problematic if the liquid being pumped contains suspended solids such as sand or rock. The streams can deform and weaken the tubing over time, even to the point of failure. The streams can ultimately cause holes in the tubing which is expensive and time consuming to repair.

A need exists for a mechanism that can be used with sucker rod systems to minimize damage to the tubing, particularly at the point where the liquid passes through the valve rod guide. The present invention addresses this need.

SUMMARY

The present invention comprises an apparatus for diverting flow in a downhole pump and a method for using the apparatus. In one embodiment, a sucker rod lifting system includes a valve rod guide having a sleeve that helps divert fluid as it passes through the rod guide to minimize damage to the system tubing. The diverter sleeve may encircle discharge ports on the valve rod guide such that fluid discharging through the ports is directed upwardly past the sleeve and out a discharge gap on the upper end of the guide. Used in this manner, the diverter sleeve prevents the fluid from damaging system tubing as it moves through the rod guide.

The present invention now will be described more fully hereinafter with reference to the accompanying drawings, which are intended to be read in conjunction with both this summary, the detailed description and any preferred and/or particular embodiments specifically discussed or otherwise disclosed. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of illustration only and so that this disclosure will be thorough, complete and will fully convey the full scope of what has been invented by the inventor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic layout of a conventional valve rod guide in a sucker rod lifting system.

FIG. 2 is a series of internal views of tubing used with a conventional valve rod guide in a sucker rod lifting system.

FIG. 3 is a diagrammatic layout of an improved valve rod guide in a sucker rod lifting system in accordance with the present invention.

FIG. 4 is a top perspective view of the improved valve rod guide diagrammed in FIG. 3 .

FIG. 5 is a front perspective view of the improved valve rod guide of FIG. 4 , with the diverter sleeve removed.

FIG. 6 is a front view of the improved valve rod guide of FIG. 4 , with the diverter sleeve removed.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.

Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, the words “upwardly,” “downwardly,” “rightwardly,” “leftwardly,” “upper,” and “lower” will refer to the installed position of the item to which the reference is made. The words “inwardly” and “outwardly” will refer to directions toward and away from, respectively, the geometric center of the embodiment being described and designated parts thereof. Said terminology will include the words specifically mentioned, derivatives thereof and words of a similar import.

Referring to FIGS. 1 and 2 , a conventional sucker rod lifting system typically includes tubing 2 for transporting an underground fluid 4 to an above ground location, a pump barrel 6, a pump plunger (not shown), and a sucker rod (not shown). The sucker rod may consist of a rod string portion and a valve rod portion. The valve rod portion typically connects to the plunger and is routed through a conventional valve rod guide 8. One problem with a conventional valve rod guide 8 is that fluid passing through openings on the valve rod guide 8 is directed against tubing 2, which can lead to damage to the tubing over time. FIG. 2 shows tubing 2 that was damaged as a result of fluid discharging from a conventional valve rod guide 8 against the tubing 2.

Referring to FIG. 3 , an exemplary embodiment of the present invention comprises an improved valve rod guide 10 having a diverter sleeve 15 encircling one or more discharge ports 20 on the guide 10. The fluid 25 being pumped by the sucker rod lifting system may be forced through discharge ports 20 and directed upward by the diverter sleeve 15 to a valve rod guide discharge gap 30. Diverter sleeve 15 may help direct fluid 25 so as to minimize damage to the sucker rod system tubing 35.

As best seen in FIGS. 5 and 6 , valve rod guide 10 comprises body 40 and a diverter sleeve 15. Body 40 includes a head 45 at an upper end of a column 50 and a base 55 at lower end of column 50. Base 55 comprises a socket 70 that receives an upper portion of a pump barrel 65 or a connector piece that engages barrel 65. Socket 70 may connect to barrel 65 (or the connector piece) by any number of joining mechanisms including a threaded engagement, bolted, or welding.

Body 40 may include an internal passageway 60 through which a valve rod (not pictured) can pass as it moves a plunger (not pictured) within the pump barrel 65. Passageway 60 is sized and shaped to allow the valve rod to move up and down within the passageway. It is foreseen that passageway 60 may be cylindrical (e.g., circular transverse cross section), which would approximate the shape of the valve rod in most applications. Passageway 60 may run through column 50 along the same longitudinal axis as column 50. Passageway 60 may communicate with the void formed by socket 70 and the passageway 60 may run continuously through column 50 and head 45.

As best seen in FIGS. 3-5 , body 40 may include a head 45 located atop column 50. Head 45 may be generally cylindrical with a two raised members 75 extending upwardly on opposite sides of the head. Between the raised members 75 is a channel 80 running across the upper portion of head 45. The channel 80 runs transversely across the central portion of head 45. The raised members 75 and channel 80 form a fork arrangement which can engage other parts of the sucker rod lifting system. The fork arrangement of members 75 and channel 80 may act as a clutch when engaging other parts of the system.

Body 40 may also include one or more discharge ports 20. Ports 20 may be located between base 55 and column 50. In an exemplary embodiment, ports 20 are located on an annular sloped surface 85 that connects base 55 to column 50. Surface 85 is sloped due to connecting base 55 to column 50, wherein base 55 has a larger diameter than column 50. Each port 20 comprises a channel 90 through surface 85 such that the port 20 is in flow communication with the void formed in socket 70. The channel 90 may be configured in any number of ways including a channel 90 that is generally perpendicular to surface 85 or a channel 90 that is generally parallel to column 50 (i.e., the channel is not perpendicular to surface 85). The fluid 25 being pumped may flow through and discharge from ports 20 in a direction that is generally aligned with the direction of channel 90. In other words, if channel 90 is generally parallel to column 50, fluid 25 will generally flow through and discharge from ports 20 parallel to column 50. If channel 90 is generally perpendicular to surface 85, fluid 25 will generally flow through and discharge from a port 20 perpendicular to surface 85.

As shown in FIGS. 3-6 , valve rod guide 10 further comprises a diverter sleeve 15 encircling discharge ports 20. Diverter sleeve 15 helps protect tubing 35 in the system by absorbing the impact of fluid 25 (including any solid particulate therein) as it flows out of discharge ports 20. This helps prevent damage to the tubing 35 due to the repeated impact of fluid 25 on the tubing wall proximate ports 20. Sleeve 15 may attach to body 40 at a location below ports 20 and extend upwardly to a location proximate head 45. Sleeve 15 may attach to body 40 in any number of ways including removably or permanently attaching to base 55. For example, as shown in FIGS. 3, 5 and 6 , sleeve 15 may threadedly engage the upper portion of base 55 at a location proximate surface 85. If is foreseen that sleeve 15 could be attached in different ways, such as fastening or welding, or it could be formed integral to body 40. Sleeve 15 could also attach to different locations on body 40 such as a lower portion of base 55.

As best seen in FIG. 3 , sleeve 15 may extend upwardly and terminate in a lip 95 proximate head 45. The exact location of lip 95 with respect to head 45 will depend on the application and the fluid 25 being pumped. The space between lip 95 and head 45 may be referred to as discharge gap 30. Discharge gap 30 is the space through which fluid 25 passes as it is being pumped. Head 45 may include a chamfer 99 or radiused underside to create a larger gap 30 and help with the flow of fluid 25. As described in more detail below, fluid 25 flows out of discharge ports 20 and travels between column 50 and sleeve 15 until passing through gap 30 and into the system tubing 35. The size of gap 30 will depend on the application and the type of fluid 25. It is foreseen that a gap of approximately one-half inch would be suitable for many applications.

To use the present invention, valve rod guide 10 is installed in a sucker rod lifting system. It may be installed by first routing a valve rod through passageway 60 of the valve rod guide 10 such that the rod extends through socket 70 and column 50 and past head 45. The upper end of the valve rod may be connected to the rod string component of the system. The lower end of the valve rod may be connected to the plunger component of the system. The plunger may be inserted into barrel 65 and the socket 70 of valve rod guide 10 may be connected to the upper end of barrel 65 (or a connector piece that engages the barrel). Barrel 65, valve rod guide 10, and the valve rod are all located within tubing 35.

As the valve rod moves up and down, the plunger moves up and down. During the downstroke, the plunger moves into barrel 65, which displaces fluid 25 into the plunger. during the upstroke, the plunger lifts fluid 25 up and out of barrel 65 into socket 70. As the plunger approaches the top of its stroke, fluid 25 is forced out of socket 70 and through discharge ports 20. After flowing out of discharge ports 20, fluid 25 travels between column 50 and sleeve 15 until passing through gap 30 and into the system tubing 35. Once fluid 25 is in tubing 35, it continues to be pumped up to its above ground collection point.

It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown. 

1. In a sucker rod fluid lifting system wherein a sucker rod has a rod string portion and a valve rod portion and tubing for accommodating the flow of fluid in said system, the improvement comprising a valve rod guide, said guide having a diverter sleeve that engages one or more discharge ports located on said guide wherein fluid being pumped by said system is forced through said ports and directed by said sleeve to a valve rod guide discharge gap, and wherein said diverter sleeve assists in directing the fluid to minimize damage to the sucker rod system.
 2. The invention in claim 1 wherein the valve rod guide comprises a body and said diverter sleeve, said system including a head at the upper end of a column and a base at the lower end of the column, said base being connected to a portion of a pump barrel and means for connecting said body to said barrel.
 3. The invention as in claim 2 wherein said head has two raised members on opposite sides of said head and a channel extending between the raised members, said raised members and said channel forming a fork capable of engaging portion of the system and acting as a clutch when engaging said system portions.
 4. The invention as in claim 3 wherein said valve rod guide is installed in said system, and wherein said system includes system tubing for directing the travel of fluid flow within said system, said barrel, said valve rod guide and said rod being located within said system tubing for assisting in directing the travel of said fluid so that after the fluid flows out of a discharge port and between the columns, the fluid flow continues to be pumped to its collection point. 